Does a phase shift occur in the current and voltage together or individually, with an inductive and capacitive load?
So I know that a phase shift (reactance) in an inductive load causes the current to be phase shifted and in a capacitive load the voltage to be phase shifted, which creates reactive power.
But I thought about it a bit more and came to the hypothesis that with an inductive or capacitive load both parameters (current and voltage) are phase shifted (in the case of alternating current).
For example, in a circuit where there is an electric coil and it is operated with alternating current.
When this alternating current flows through this coil, an inductance is created, which creates a reactance in the current. But when the current direction changes, self-induction occurs in the coil, causing a current flow in the opposite direction, as well as a voltage. This would then not only cause the current to be phase-shifted, but also the voltage, right?
According to my hypothesis, this can be applied to the capacitor (capacitive load) in the same way.
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Phase shifts are relative to the reference value. A current lagging the voltage is, in context, a voltage leading the current. The reference value is crucial here. The circuit type is also important.
Max is watching Lisa. From Max's perspective, Lisa is moving past him at 30 km/h. From Lisa's perspective, Max is moving away from her at 30 km/h.
Inductance is based on the principle of inertia. An accelerating mass tends to maintain its motion. A mass at rest tends to remain in its resting position. In both states, they strive to maintain their respective flux and counteract the opposing force. In inductance, this occurs due to the change in magnetic flux, which induces a voltage that counteracts the voltage driving the primary current. Think of it as an additional hurdle. The driving voltage wanted to increase in order to move a higher current at the same time. It could increase. But with every change in its magnitude, the hurdle also changed, so that the current could never increase at the same times, but only with a delay. But this never changed the natural course of the driving voltage. Also, there was never a moment when electrons moved in both directions (we are not considering atomic oscillations right now).
With capacitance, it's exactly the other way around, but the principle of electrical inertia remains. The voltage can't change abruptly, while the current flows gradually from one plate to the other.
Normally, the voltage and current in alternating current are sinusoidal and congruent.
For inductive components, the curves shift in one direction (up to a maximum of 90°), while for capacitive components, the curves shift in the other direction (up to a maximum of 90°). If only a capacitor or coil is present, the shift is exactly 90°; if a resistor is present, the shift is less.
What you use as a reference—whether you look at how the voltage changes in relation to the current or the other way around—is really up to you. In a closed circuit, voltage and current are always connected via the (alternating current) resistance.
The "phase shift" approach only works if you consider alternating current without a temporal beginning and end… that is, only a section. Other things happen during the switching process (on or off).